Surface mount supplies carrier tape is used to transport components (e.g., electrical components such as resistors, capacitors, or integrated circuits) from a component manufacturer to a different manufacturer that assembles the components into new products, typically by having automated assembly equipment sequentially remove components from the carrier tape and assemble them into the new products. Such carrier tape is a polymeric strip that has been formed to have wall portions defining a series of identical pockets at predetermined uniformly spaced intervals along its length, which pockets are shaped to closely receive identical components the tape is adapted to transport (e.g., which pockets could, for example, have rectangular or generally "I" or "T" shapes in the plane of the strip, and could have flat or rounded bottoms to accommodate the shape of the components), which strip normally also has through openings uniformly spaced along one side to receive a drive sprocket by which the strip can be driven and to provide indexing holes that can be used for accurately locating the pockets along the tape with respect to assembly equipment. Typically, the carrier tape is manufactured in a first manufacturing location, wound on a reel and transported to the supplier of the components it is intended to transport. The component supplier unwinds the carrier tape from the reel, fills the pockets along the carrier tape with components, adheres a removable cover strip along the carrier tape over the component filled pockets, winds the component filled carrier tape with the attached cover strip onto a reel, and sends it to the user who feeds it from the reel into the assembly equipment which removes the components.
While such carrier tape can be formed by continuous injection molding, it is more commonly formed from an initially flat polymeric heated thermoplastic strip using a tool to form the pockets (e.g., male and female die sets, or a male or a female die over which the strip is vacuum formed) that produces a slight draft or taper in the side wall portions defining the pockets so that the bottom wall portions defining the pockets, while having generally the same shape as the inlets to the pockets, are slightly smaller in area than the inlets to the pockets. Such draft both allows the carrier strip to be easily released from the tool by which the pockets are formed, and provides a self centering effect to subsequently facilitate positioning components in the pockets. Unfortunately, however, the draft in the side wall portions of the pockets also causes problems when the embossed carrier tape is wound on a reel prior to having the components inserted into the pockets. One of these problems is the tendency for the side wall portions defining the pockets in one wrap of the carrier tape on the reel to "nest" in or enter the pockets in the wrap of carrier tape beneath it, which causes the outer surfaces of the side wall portions in that one wrap to frictionally engage the inner surface of the side wall portions defining the pockets in the wrap beneath it. Such frictional engagement can be very firm because of the draft angle at which those wall portions are disposed which provides a locking taper relationship between the engaging surfaces. A large force is then required to pull apart the nesting wraps of the carrier tape, which force can deform the carrier tape so that it will not be properly handled by automated equipment by which components are loaded into it or by which components are removed from it. Another one of these problems is the tendency for the side wall portions defining the pockets along one side of one wrap of the carrier tape on the reel to enter the pockets in the wrap of carrier tape beneath it while the side wall portions along the other side of that wrap are supported along the uppermost surface of the carrier tape. Under these conditions, pressure from outer wraps of the strip material in the reel can cause plastic deformation of the strip so that it is no longer straight when it is unwound from the reel and will not be properly handled by automated equipment by which components are loaded into it or by which components are removed from it.